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1.
Tetrabromobisphenol-A (TBBP-A), hexabromocyclododecane (HBCD) and its degradation products were determined in 34 human milk samples from Birmingham, UK. TBBP-A was detected in 36% of samples (average=0.06 ng g(-1) lw), with HBCDs detected in all samples (average ΣHBCDs=5.95 ng g(-1) lw). α-HBCD comprised 62-95% ΣHBCDs while β- and γ-HBCD constituted 2-18% and 3-33% respectively. Enantioselective enrichment of (-)-α-HBCD (average enantiomer fraction=0.29) was observed indicating potential enantioselectivity associated with HBCD absorption, metabolism and/or excretion. The degradation products pentabromocyclododecenes (average=0.04 ng g(-1) lw; n=9) and tetrabromocyclododecadienes (average=0.15 ng g(-1) lw; n=25) were detected for the first time in human tissues. Average exposures of a nursing infant to ΣHBCDs and TBBP-A (35 and 1 ng kg(-1) bw day(-1) respectively) via breast milk exceeded upper-bound dietary intakes of both UK adults and toddlers. Using a simple pharmacokinetic model, intakes of UK adults via inhalation, diet and dust ingestion were converted to predicted body burdens. Predictions compared well with those observed for HBCDs but observed body burdens of TBBP-A exceeded predictions. This may indicate the human half-life of TBBP-A is greater than observed previously, that intakes may be underestimated, or that concentrations reported here reflect recent elevated episodic exposure.  相似文献   

2.
To enlarge the possibilities of using organisms of the soil fauna to assess the bioaccumulative potential of chemicals, the kinetic of soil cadmium (Cd) transfer to the terrestrial gastropod Helix aspersa was investigated under laboratory conditions during a long-term experiment (6 months). During the exposure phase (3 months), juvenile snails were subjected to three different concentrations of Cd spiked in artificial ISO soil (ISO 0, 20 and 100 mg Cd kg(-1)) and to a field soil (ME4) industrially contaminated by 20 mg Cd kg (-1). For both soils, internal steady-state Cd concentrations were reached in the viscera of the snails, the main storage organ for Cd, after 2 weeks of exposure whatever the Cd concentration in soil. The equilibrium concentrations in the viscera were 0.7 (+/-0.1), 11.3 (+/-2.4), 73.3 (+/-4.8) and 6.3 (+/-1.3) mg Cd kg(-1) dry mass for ISO 0, ISO 20, ISO 100 and ME4, respectively. During the depuration phase (3 months), from 0 to 52% of the accumulated Cd in the viscera were removed by excretion or relocation in the foot. However, the snails were not able to depurate down to initial concentrations. Data were modelled by integrating a specific growth rate constant into one-compartment toxicokinetic models. This allowed the calculation of Cd uptake rates that can be used as indicators of metal bioavailability. Since this parameter was found to be lower for snails exposed to the field soil ME4, we concluded that lower Cd bioavailability in this field soil was responsible of the lower transfer to the snails compared to the ISO 20 soil, even though they were polluted to similar extents. Internal validation showed that the toxicokinetic models could be applied for predictive purposes, promising for the development of a bioaccumulation directive for terrestrial environment.  相似文献   

3.
Dairy feeding systems in many semi-arid countries are based on imported concentrates and forages. This has economic and ecological implications given the increase in global feed prices and greenhouse gas (GHG) emissions from land use change. This paper aims to explore alternative dairy feeding systems under semi-arid conditions, using Jordan as an example. The feedings systems under investigation vary in their share of food industry by-products (replacing concentrates in the diet) and are compared against the current concentrate-based feeding systems. The systems are evaluated against three criteria: their nutritional value, their impact on the cost of milk production, and their GHG mitigation potential. Feed samples from eleven food industry by-products and ten conventional feeds were collected from food factories and from three typical dairy farms, representing the typical large-, medium- and small-scale farm types, respectively. Feed samples were analysed for their chemical composition and metabolisable energy contents. In addition, economic and production farm data were collected and entered into a model for GHGs calculation and economic evaluation. The results suggest that inclusion of locally available food industry by-products in the rations of milk cows in semi-arid production systems can be instrumental in reducing production costs and mitigating GHG emissions. Cost of milk production in the model farms can be lowered by up to 14 %; mitigation of CO2 eq. emission ranged between 70 and 290 g CO2 eq./kg milk. The degree to which these benefits can be reaped is positively related to the level of inclusion of by-product feeds in lactating cows’ diets.  相似文献   

4.
In order to assess the long-term impact of persistent organic contaminants such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) it is important to be able to quantify historical exposure. An understanding of past exposure is not only important to place our current body burdens in perspective, but is useful in assessing our potential future exposure. Unfortunately, very few direct measurements of our main source of exposure (i.e., food) over the past decades are available. This study attempts to reconstruct the historical exposure of the UK population to PCDD/Fs using a combination of emission estimates, information on environmental temporal trends derived from sediment cores and archived materials, and environmental/human fate modelling. Predicted adipose and blood lipid concentrations for a typical cross section of the population are derived over time (1920-2000), which is compared with measured data. The approach has been tested with two PCDDs and two PCDFs and showed encouraging agreement with measured data. Certain parts of the modelling methodology have been highlighted where there is still poor understanding of the processes governing fate and behaviour. These areas are discussed and recommendations for future improvements are made. The paper thus represents an initial modelling approach which defines both the historical (1920-present) and future (present-2020) fate of PCDD/Fs in the UK population.  相似文献   

5.
6.
Oil palm industries produce an enormous quantity of lignocellulosic biomass; in the form of large leaves of palm tree, pruned fronds (OPF) and oil palm trunks (OPT) at the plantations site. Besides this, the processing of fresh fruit bunches in the oil mills generates empty fruit bunches (EFB), shells, kernel cake and mesocarp fibers. The proper management of this burgeoning waste and its disposal is an ardent task and creates environmental hazards. In order to deal with the biomass residues, the urgent need is that it should be transformed into resources with industrial utility. As the economic development has resulted in the significant increased demand for paper, the industry is looking for eccentric sources to fulfill the requirement. The pulp and paper industry preferred use of coniferous and deciduous trees for papermaking because their cellulose fibers in the pulp make durable paper. With improvements in pulp processing technology, fibers of almost any non-wood of plants species like bamboo, cereal straw, sugarcane, flax, hemp and jute can be used for paper pulp. Substituting this lignocellulosic material can reduce the burden on forest while supporting the natural biodiversity. The present review deals with the possibilities of using oil palm biomass as a raw material for pulp and papermaking, as this would ameliorate its waste management problem. The potential of oil palm biomass and the challenges regarding its use in papermaking are discussed. The use of oil palm biomass will apparently prove that the oil palm industry is ecofriendly in every aspect of its activities and aid in sustainability of forest ecosystem.  相似文献   

7.
In Northern Namibia, the climate is highly polarised between dry and wet seasons, and local communities have lived with these varying weather extremes for centuries. However, the recent changes in socio-environmental dynamics—associated with urbanisation, inappropriate spatial planning, and population growth—have disturbed the river system in the area. These changes, together with torrential seasonal rains, have aggravated the social impacts of the flood events. By using various qualitative and quantitative data sources, and comparative analyses between the flood dynamics in urban and rural environments, this research studies local residents’ coping strategies to endure the irregular flood events from the perspective of socio-ecological resilience. Particular interest is placed on the learning processes that enhance the residents’ capability to cope and the role of indigenous knowledge. Indigenous knowledge (IK) has been emphasised as a source of resilience in both theory and practice, as it is built upon learning from past experiences of natural hazards. The findings reveal that the floods are a result of complex and relational development without the necessary linear relationship between the causes and effects. The abrupt socio-ecological changes, together with the multiple stressors related to poverty, have made residents more vulnerable to the flood events and attenuated the communities’ coping strategies based on IK. Instead of focusing on the communities’ capacity to self-organise, the focus of resilience building needs to be directed to emphasising the broader socio-political processes, which are making the communities vulnerable in the first place.  相似文献   

8.
The weight of scientific evidence suggests that human activities are noticeably influencing the world's climate. However, the effects of global climate change will be unevenly spread, due to local variations in vulnerability and adaptive capacity. Using downscaled projections of future UK climates over the next 50 years, this paper investigates the impacts of, and possible responses to, climate change in one small area in eastern England, selected as a test-bed for sustainable agriculture. It shows that local agricultural systems are vulnerable to changes in the climate. At present, however, these considerations have a limited effect on agricultural operations, which are mainly driven by short-term events and 'non-climate' policies, such as agricultural price support. The capacity of agricultural systems to adapt successfully to climate change will be determined by the ability of producers to integrate climate change into their planning strategies with a view to ultimately ensuring sustainable agricultural practices in the long term. Electronic Publication  相似文献   

9.
This paper presents a review of approaches that may be useful for the selection of solvents in the early stages of process development for the synthesis of active pharmaceutical ingredients. Characteristics of the methodologies and their applicability in early stages are explored. Early stages of development are recognised as ideal for detecting benefits and issues regarding the use of solvents. The ??system?? concept is introduced for the evaluation and selection of solvents in pharmaceutical processes; this concept does not yet seem to be widely utilised within the fine chemicals and pharmaceutical industries. System analysis is considered an important tool for viewing solvent selection from a holistic perspective. Hence, approaches suitable for the early stages of development and considering a holistic perspective might deliver more sustainable processes. The evolution of the synthesis of Ibuprofen API is used to illustrate this concept.  相似文献   

10.
The tannery industry in Hazaribag,which is one of the most polluted areas in Dhaka City,produces a huge quantity of wastes every day.Without treatment,these are discharged into the Buriganga River and pollute the surrounding environment.This article examines the impacts of tannery wastes on workers’health and the environment in that particular area.As part of the methodology,a semi-structured interview was conducted in order to obtain quantitative data and 112 respondents were interviewed using purposive sampling.The findings of the study indicate that tannery wastes affect the environment severely,causing ecological imbalance and the spreading of different kinds of fatal and contagious disease among the tannery workers and other individuals.Moreover,the current waste management system of the Hazaribag tannery industries is very suspect due to outdated technology,defective drainage systems,lack of financial input,and the exploitative attitude of their owners.The findings also indicate that tannery workers are unaware of the effects of tannery waste as they choose not to wear personal protective equipment in the workplace.This empirical study helps policy makers implement appropriate measures to raise awareness,among both owners and workers,that can influence changes in the public’s attitude and reduce environmental pollution to a great extent.Although considerable research has been undertaken focusing on tannery waste impact assessment,less attention has been paid to the issue of workers’health.Therefore,both governments and policy makers can benefit from the findings of this study.  相似文献   

11.
The tannery industry in Hazaribag, which is one of the most polluted areas in Dhaka City, produces a huge quantity of wastes every day. Without treatment, these are discharged into the Buriganga River and pollute the surrounding environment. This article examines the impacts of tannery wastes on workers’ health and the environment in that particular area. As part of the methodology, a semi-structured interview was conducted in order to obtain quantitative data and 112 respondents were interviewed using purposive sampling. The findings of the study indicate that tannery wastes affect the environment severely, causing ecological imbalance and the spreading of different kinds of fatal and contagious disease among the tannery workers and other individuals. Moreover, the current waste management system of the Hazaribag tannery industries is very suspect due to outdated technology, defective drainage systems, lack of financial input, and the exploitative attitude of their owners. The findings also indicate that tannery workers are unaware of the effects of tannery waste as they choose not to wear personal protective equipment in the workplace. This empirical study helps policy makers implement appropriate measures to raise awareness, among both owners and workers, that can influence changes in the public’s attitude and reduce environmental pollution to a great extent. Although considerable research has been undertaken focusing on tannery waste impact assessment, less attention has been paid to the issue of workers’ health. Therefore, both governments and policy makers can benefit from the findings of this study.  相似文献   

12.
We downscale the results of a global tourism simulation model at a national resolution to a regional resolution. We use this to investigate the impact of climate change on the regions of Germany, Ireland and the UK. Because of climate change, tourists from all three countries would spend more holidays in the home country. In all three countries, climate change would first reduce the number of international arrivals—as Western European international tourist demand falls—but later increase numbers—as tourism demand from increasingly rich tropical countries grows. In Ireland and the UK, the regional pattern of demand shifts is similar to the international one: tourism shifts north. In Germany, the opposite pattern is observed as the continental interior warms faster than the coast: tourism shifts south.
Jacqueline M. HamiltonEmail:
  相似文献   

13.
The aim of this paper was to present the contribution of the sugar cane industry to reduce carbon dioxide emissions in the energy sector. Mauritius is taken as a case study. Sugar cane was introduced in Mauritius during the seventeenth century and production of sugar started around 60 years later. Since then, the cane industry has been one of the economic pillars of the country. Bagasse, a by-product of sugar cane, is used as fuel in cogeneration power plants to produce process heat and electricity. This process heat and the generated electricity are used by an annexed sugar mills for the production of sugar, while the remaining electricity is exported to the national grid. In fact, Mauritius is a pioneer in the field of bagasse-based cogeneration power plant; the first bagasse-based cogeneration power plant that was commissioned in the world was in Mauritius in 1957. The contribution of the cane industry in the electricity sector has been vital for the economic development of Mauritius and also in terms of mitigating carbon dioxide emissions by displacing fossil fuels in electricity generation, as bagasse is classified as a renewable source. Data obtained from Statistics Mauritius on electricity production for the past 45 years were analysed, and carbon dioxide emissions were calculated based on international norms. It is estimated that savings on heavy fuel oil importation were by 1.5 million tons of oil—representing a value of 2.9 billion dollars—thus avoiding 4.5 million tons of carbon dioxide emissions. This figure can be further increased if molasses, a by-product of sugar cane juice, is used to produce bio-ethanol to be used as fuel in vehicles.  相似文献   

14.
Following an intensive survey of domestic radon levels in the United Kingdom (UK), the former National Radiological Protection Board (NRPB), now the Radiation Protection Division of the Health Protection Agency (HPA-RPD), established a measurement protocol and promulgated Seasonal Correction Factors applicable to the country as a whole. Radon levels in the domestic built environment are assumed to vary systematically and repeatably during the year, being generally higher in winter. The Seasonal Correction Factors therefore comprise a series of numerical multipliers, which convert a 1-month or 3-month radon concentration measurement, commencing in any month of the year, to an effective annual mean radon concentration. In a recent project undertaken to assess the utility of short-term exposures in quantifying domestic radon levels, a comparative assessment of a number of integrating detector types was undertaken, with radon levels in 34 houses on common geology monitored over a 12-month period using dose-integrating track-etch detectors exposed in pairs (one upstairs, one downstairs) at 1-month and 3-month resolution. Seasonal variability of radon concentrations departed significantly from that expected on the basis of the HPA-RPD Seasonal Correction Factor set, with year-end discontinuities at both 1-month and 3-month measurement resolutions. Following this study, monitoring with electrets was continued in four properties, with weekly radon concentration data now available for a total duration in excess of three and a half years. Analysis of this data has permitted the derivation of reliable local Seasonal Correction Factors. Overall, these are significantly lower than those recommended by HPA-RPD, but are comparable with other results from the UK and from abroad, particularly those that recognise geological diversity and are consequently prepared on a regional rather than a national basis. This finding calls into question the validity of using nationally aggregated Seasonal Correction Factors, especially for shorter exposures, and the universal applicability of these corrections is discussed in detail.  相似文献   

15.
The East China Seas (ECSs) are the receptors of the land-based persistent organic pollutants (POPs), such as polybrominated diphenyl ethers (PBDEs) mainly from China through atmospheric deposition driven by the East Asian winter monsoon and fluvial discharge (e.g., Yangtze River and Yellow River), making the offshore sediments to be a good proxy to reconstruct history of those pollutants in China. In this work, four well-placed sediment cores were extracted from the mud areas in the ECSs, and the 210Pb-dated cores were analyzed to yield historical concentration profiles of PBDEs in the area. The results showed that there was a persistent increase from 1970s and almost no clear sign in the decline of PBDEs until recently in China. More importantly, there was a faster increase of PBDEs from 1990s in China; while this period was just shown as gradually leveling off or even declining trends in developed countries. The persistently increasing trend of PBDEs in China since 1990s could be largely due to the booming of the manufacturing industry and unexpectedly transfer of PBDE pollution from developed countries to China. Besides, the relative high concentrations and fluxes of PBDEs in the core from coastal ECS located near a well-known electrical/electronic waste (e-waste) recycling area suggests an important contribution of PBDE emissions from recycling centers of e-waste in China. Although efforts in environmental monitoring of PBDE contamination have been substantially increased over the last decade, China is still lagging behind in terms of nationwide regulation of PBDE usage and treatment of disposal PBDE-containing products.  相似文献   

16.
The UK Climate Change Act (CCA) mandates an 80 % reduction in CO2 emissions by 2050. It is estimated that 3.2 M tonnes pa CO2 results from travel-related NHS business. The acquisition of an electric bicycle to replace a car for both commuting and home visits allowed comparison of fuel use and CO2 emissions over a 4-year period. The switch to the use of the electric bicycle reduced the average annual petrol use by 329 l, the energy consumption by 3,140 kWh and the CO2 released by 748 kg a year. Wider adoption of electric bicycles in urban General Practice will contribute to the requirements of the CCA though to have a significant effect on the current estimated commuting-related carbon footprint of the NHS (0.76 MT pa) would require two-thirds of the workforce to abandon their cars in favour of electric bicycles.  相似文献   

17.
There is mounting evidence that climate change is already having an impact on the wine industry, with effects being region specific. In order to understand the capacity of regional wine sectors to adapt to changing climate, it is useful to document the conditions that are important to producers and to identify adaptation and management strategies that are employed in the industry. This paper analyzes climatic conditions and adaptation strategies in the wine region of Prince Edward County Ontario, Canada. Wine producers identified the climate variables most important to their operations and described strategies they use to manage climate-related conditions. The identified variables were analyzed for trends over the study period 1987–2011, and interview data were analyzed in order to categorize adaptive strategies. Results indicate that the wine sector is very sensitive to climate, and the region is already experiencing the effects of climate change, especially with regard to increasing growing season mean minimum daily temperatures, increasing total summer rainfall, and later onset of fall frosts. Adaptive strategies employed by producers are largely learned though collaborative efforts and trial and error. The adaptations are mostly tactical and reactive in the short term, but with continued climate change, these strategies may develop into strategic, anticipatory measures. Climate change has the potential to present both challenges and opportunities to Prince Edward County wine producers, and adaptations will continue to require strong networking and collaborative efforts.  相似文献   

18.
On the basis of the fifth Chinese total diet study (TDS) performed in 2011, the dietary exposure of the Chinese population to novel brominated flame retardants (NBFRs) was assessed. Six NBFRs were determined in 80 composite samples from four animal origin food groups and 29 pooled human milk samples. Based on gas chromatography-negative chemical ionization mass spectrometry (GC-NCI/MS) analysis, the levels of the total NBFRs ranged from < LOD to 70.2 ng/g lipid weight (lw) in food composites and from 2.48 to 23.9 ng/g lw in human milk samples. Decabromodiphenyl ethane (DBDPE), with mean levels of 9.03 ng/g lw in food composites and 8.06 ng/g lw in human milk, was the most abundant compound in the total NBFRs. No obvious spatial distribution patterns in China were observed in food samples or human milk. The average estimated daily intake (EDI) of total NBFRs via food consumption for a “standard Chinese man” was 4.77 ng/kg bodyweight (bw)/day, with a range of 0.681 to 18.9 ng/kg bw/day. Meat and meat products were the main dietary source of NBFRs, although levels of NBFRs in aquatic food were found to be the highest among the four food groups. The average EDI of total NBFRs for nursing infants was 38.4 ng/kg bw/day, with a range of 17.4 to 113 ng/kg bw/day, which was approximately eight-fold higher than the EDI for adults, suggesting the heavy body burden of NBFRs on nursing infants. The levels and EDI of DBDPE in the present study were similar to or higher than those of legacy BFRs (i.e., PBDEs and HBCD) in the TDS 2007, indicating that DBDPE, as a main alternative to PBDEs, might have become the primary BFR used in China.  相似文献   

19.
This paper presents results of a model test carried out within the framework of the COMETES project (EU). The aim of the work was to change the structure of the MOIRA lake model for radiocesium so that it can be applied more generally for, in principle, all types of radionuclides and heavy metals. This general lake model is used within the MOIRA decision support system (DSS; MOIRA and COMETES are acronyms for EU-projects). The model is based on a set of differential equations and a specific modelling structure. It incorporates all important fluxes to, from and within lakes in a general manner. Yet the model is driven by a minimum of variables accessible from standard maps and monitoring programs. The model can be separated into two parts, a general part with equations applicable for all types of water pollutants and a substance-specific part. This model has previously been validated for 137Cs from many lakes covering a wide domain and yielded excellent predictive power. The alterations discussed in this work are meant to be general and radiostrontium is used as a typical element. Radiostrontium is known to be more mobile than radiocesium and all abiotic parts of the model handling fixation and mobility have been altered. The new model for 90Sr has been critically tested using data from four lakes heavily contaminated with 90Sr from the Kyshtym accident in the Southern Urals, Russia, using empirical data from a period from 1958 to 1995 for 90Sr in fish (here goldfish), water and sediments.  相似文献   

20.
Increasing populations are causing an increase in food demands, and the area of cultivated land expands every year. Inappropriate land transition from ecology to production results in the constant decline of the ecological security level and influences the regional sustainable development. Adjusting unreasonable land use mode and reconstructing natural land cover are important ways to maintain and improve the ecological environment. Also reclaiming farmland as areas for forests and grasslands (FRFG) is another way. Successful implementation of FRFG in China is the result of comprehensive effect of the multi-scales driving forces. This paper analyses the driving forces of FRFG in China on a national (country) -regional (province) - local (county) - household (farmer) level scale, and the results are: driving forces at the national scale include ecological and food security and the western development of China; at the regional scale, ecological and economic benefits become the main factors to influence the dimension of FRFG under the same policy. The driving forces can be divided into 6 types: industrial structure adjustment, water source protection, flood prevention, the Three-Gorge Project protection, reduction of the amount of sediment flowing into the Yellow River and wind erosion desertification prevention. The driving forces at the local scale can be divided into 12 types with developing leading industries, increasing farmers' income and improving agricultural production conditions as the main types; at the household scale, the national policy meeting farmers' demands and the optimization of individual interests are all driving forces.  相似文献   

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